Fifteen samples,of size 100 were collected and a total of 96 nonconforming items were found.The 3-sigma upper control limit for a p-chart would be:
A)0.066.
B)0.083.
C)0.137.
D)0.254.

Question

Quizplus · Accepted Answer

The formula for the upper control limit of a p-chart is:

UCLp = p + 3√((p(1-p))/n)

where p is the overall proportion of nonconforming items, and n is the sample size.

To calculate p, we divide the total number of nonconforming items (96) by the total number of items inspected (15*100 = 1500):

p = 96/1500 = 0.064

Substituting this value and n=100 into the formula, we get:

UCLp = 0.064 + 3√((0.064(1-0.064))/100) = 0.137

Therefore, the answer is C.

Fifteen Samples,of Size 100 Were Collected and a Total of 96